Excess nutrient loads to Lake Taihu

Opportunities for nutrient reduction

Mengru Wang*, Maryna Strokal, Peter Burek, Carolien Kroeze, Lin Ma, Annette B.G. Janssen

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

11 Citations (Scopus)

Abstract

Intensive agriculture and rapid urbanization have increased nutrient inputs to Lake Taihu in recent decades. This resulted in eutrophication. We aim to better understand the sources of river export of total dissolved nitrogen (TDN) and phosphorus (TDP) to Lake Taihu in relation to critical nutrient loads. We implemented the MARINA-Lake (Model to Assess River Inputs of Nutrients to seAs) model for Lake Taihu. The MARINA-Lake model quantifies river export of dissolved inorganic and organic N and P to the lake by source from sub-basins. Results from the PCLake model are used to identify to what extent river export of nutrients exceeds critical loads. We calculate that rivers exported 61 kton of TDN and 2 kton of TDP to Lake Taihu in 2012. More than half of these nutrients were from human activities (e.g., agriculture, urbanization) in Sub-basins I (north) and IV (south). Most of the nutrients were in dissolved inorganic forms. Diffuse sources contributed 90% to river export of TDN with a relatively large share of synthetic fertilizers. Point sources contributed 52% to river export of TDP with a relatively large share of sewage systems. The relative shares of diffuse and point sources varied greatly among nutrient forms and sub-basins. To meet critical loads, river export of TDN and TDP needs to be reduced by 46–92%, depending on the desired level of chlorophyll-a. There are different opportunities to meet the critical loads. Reducing N inputs from synthetic fertilizers and P from sewage systems may be sufficient to meet the least strict critical loads. A combination of reductions in diffuse and point sources is needed to meet the most strict critical loads. Combining improved nutrient use efficiencies and best available technologies in wastewater treatment may be an effective opportunity. Our study can support the formulation of effective solutions for lake restoration.

Original languageEnglish
Pages (from-to)865-873
JournalScience of the Total Environment
Volume664
DOIs
Publication statusPublished - 10 May 2019

Fingerprint

Nutrients
Lakes
critical load
Rivers
nutrient
lake
river
Phosphorus
Nitrogen
phosphorus
point source
nitrogen
Fertilizers
Sewage
Catchments
Agriculture
urbanization
sewage
basin
fertilizer

Keywords

  • Critical nutrient loads
  • MARINA-Lake
  • Nutrient sources
  • PCLake model
  • River export of nutrients
  • Sub-basins

Cite this

@article{75c07781f87548fd84eb0f0f454fda64,
title = "Excess nutrient loads to Lake Taihu: Opportunities for nutrient reduction",
abstract = "Intensive agriculture and rapid urbanization have increased nutrient inputs to Lake Taihu in recent decades. This resulted in eutrophication. We aim to better understand the sources of river export of total dissolved nitrogen (TDN) and phosphorus (TDP) to Lake Taihu in relation to critical nutrient loads. We implemented the MARINA-Lake (Model to Assess River Inputs of Nutrients to seAs) model for Lake Taihu. The MARINA-Lake model quantifies river export of dissolved inorganic and organic N and P to the lake by source from sub-basins. Results from the PCLake model are used to identify to what extent river export of nutrients exceeds critical loads. We calculate that rivers exported 61 kton of TDN and 2 kton of TDP to Lake Taihu in 2012. More than half of these nutrients were from human activities (e.g., agriculture, urbanization) in Sub-basins I (north) and IV (south). Most of the nutrients were in dissolved inorganic forms. Diffuse sources contributed 90{\%} to river export of TDN with a relatively large share of synthetic fertilizers. Point sources contributed 52{\%} to river export of TDP with a relatively large share of sewage systems. The relative shares of diffuse and point sources varied greatly among nutrient forms and sub-basins. To meet critical loads, river export of TDN and TDP needs to be reduced by 46–92{\%}, depending on the desired level of chlorophyll-a. There are different opportunities to meet the critical loads. Reducing N inputs from synthetic fertilizers and P from sewage systems may be sufficient to meet the least strict critical loads. A combination of reductions in diffuse and point sources is needed to meet the most strict critical loads. Combining improved nutrient use efficiencies and best available technologies in wastewater treatment may be an effective opportunity. Our study can support the formulation of effective solutions for lake restoration.",
keywords = "Critical nutrient loads, MARINA-Lake, Nutrient sources, PCLake model, River export of nutrients, Sub-basins",
author = "Mengru Wang and Maryna Strokal and Peter Burek and Carolien Kroeze and Lin Ma and Janssen, {Annette B.G.}",
year = "2019",
month = "5",
day = "10",
doi = "10.1016/j.scitotenv.2019.02.051",
language = "English",
volume = "664",
pages = "865--873",
journal = "Science of the Total Environment",
issn = "0048-9697",
publisher = "Elsevier",

}

Excess nutrient loads to Lake Taihu : Opportunities for nutrient reduction. / Wang, Mengru; Strokal, Maryna; Burek, Peter; Kroeze, Carolien; Ma, Lin; Janssen, Annette B.G.

In: Science of the Total Environment, Vol. 664, 10.05.2019, p. 865-873.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Excess nutrient loads to Lake Taihu

T2 - Opportunities for nutrient reduction

AU - Wang, Mengru

AU - Strokal, Maryna

AU - Burek, Peter

AU - Kroeze, Carolien

AU - Ma, Lin

AU - Janssen, Annette B.G.

PY - 2019/5/10

Y1 - 2019/5/10

N2 - Intensive agriculture and rapid urbanization have increased nutrient inputs to Lake Taihu in recent decades. This resulted in eutrophication. We aim to better understand the sources of river export of total dissolved nitrogen (TDN) and phosphorus (TDP) to Lake Taihu in relation to critical nutrient loads. We implemented the MARINA-Lake (Model to Assess River Inputs of Nutrients to seAs) model for Lake Taihu. The MARINA-Lake model quantifies river export of dissolved inorganic and organic N and P to the lake by source from sub-basins. Results from the PCLake model are used to identify to what extent river export of nutrients exceeds critical loads. We calculate that rivers exported 61 kton of TDN and 2 kton of TDP to Lake Taihu in 2012. More than half of these nutrients were from human activities (e.g., agriculture, urbanization) in Sub-basins I (north) and IV (south). Most of the nutrients were in dissolved inorganic forms. Diffuse sources contributed 90% to river export of TDN with a relatively large share of synthetic fertilizers. Point sources contributed 52% to river export of TDP with a relatively large share of sewage systems. The relative shares of diffuse and point sources varied greatly among nutrient forms and sub-basins. To meet critical loads, river export of TDN and TDP needs to be reduced by 46–92%, depending on the desired level of chlorophyll-a. There are different opportunities to meet the critical loads. Reducing N inputs from synthetic fertilizers and P from sewage systems may be sufficient to meet the least strict critical loads. A combination of reductions in diffuse and point sources is needed to meet the most strict critical loads. Combining improved nutrient use efficiencies and best available technologies in wastewater treatment may be an effective opportunity. Our study can support the formulation of effective solutions for lake restoration.

AB - Intensive agriculture and rapid urbanization have increased nutrient inputs to Lake Taihu in recent decades. This resulted in eutrophication. We aim to better understand the sources of river export of total dissolved nitrogen (TDN) and phosphorus (TDP) to Lake Taihu in relation to critical nutrient loads. We implemented the MARINA-Lake (Model to Assess River Inputs of Nutrients to seAs) model for Lake Taihu. The MARINA-Lake model quantifies river export of dissolved inorganic and organic N and P to the lake by source from sub-basins. Results from the PCLake model are used to identify to what extent river export of nutrients exceeds critical loads. We calculate that rivers exported 61 kton of TDN and 2 kton of TDP to Lake Taihu in 2012. More than half of these nutrients were from human activities (e.g., agriculture, urbanization) in Sub-basins I (north) and IV (south). Most of the nutrients were in dissolved inorganic forms. Diffuse sources contributed 90% to river export of TDN with a relatively large share of synthetic fertilizers. Point sources contributed 52% to river export of TDP with a relatively large share of sewage systems. The relative shares of diffuse and point sources varied greatly among nutrient forms and sub-basins. To meet critical loads, river export of TDN and TDP needs to be reduced by 46–92%, depending on the desired level of chlorophyll-a. There are different opportunities to meet the critical loads. Reducing N inputs from synthetic fertilizers and P from sewage systems may be sufficient to meet the least strict critical loads. A combination of reductions in diffuse and point sources is needed to meet the most strict critical loads. Combining improved nutrient use efficiencies and best available technologies in wastewater treatment may be an effective opportunity. Our study can support the formulation of effective solutions for lake restoration.

KW - Critical nutrient loads

KW - MARINA-Lake

KW - Nutrient sources

KW - PCLake model

KW - River export of nutrients

KW - Sub-basins

U2 - 10.1016/j.scitotenv.2019.02.051

DO - 10.1016/j.scitotenv.2019.02.051

M3 - Article

VL - 664

SP - 865

EP - 873

JO - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

ER -